Evidence for the Health Claim

Beliefs about the sequence of drinking may stem from the rate at which the body processes alcohol. The liver can only efficiently process one standard-sized alcoholic drink per hour, although men can process more alcohol per hour than women. What constitutes one drink? Twelve ounces of beer, five ounces of wine, and one shot (1.5 ounces) of hard liquor are generally equivalent in their alcohol content.

The amount of alcohol in the blood rises more quickly after drinking liquor than after drinking beer. If you drink liquor before beer, therefore, you are likely to feel the effects of the alcohol sooner. This may encourage you not to consume as much, decreasing the chances of getting sick from overdoing it. Drinking beer before liquor, on the other hand, may make you feel ill since, having had little or no immediate effect from the beer, you may be motivated to consume higher concentrations of alcohol by doing shots or mixing stronger drinks.

Some believe that because beer is carbonated, it irritates the lining of the stomach and alcohol is absorbed more quickly; however, there is limited research in support of this view. If beer is absorbed quicker because it is carbonated, then adding wine or hard liquor may lead to a greater degree of intoxication.

A more scientific explanation for the common belief is that different types of alcohol contain different amounts of compounds called congeners. Drinks that contain high quantities of congeners may increase hangover symptoms. Clear beverages like vodka, gin, and white wine contain less congeners than darker drinks like brandy, whisky, rum, and red wine. Mixing the congeners may increase stomach irritation.

Evidence Against the Health Claim

No conclusive evidence exists to support or reject claims about the ill effects of mixing different types of alcohol.  The amount of alcohol consumed in a specific time frame is what largely determines how drunk or sick you may feel.  It’s the rate at which alcohol is consumed that largely determines the degree of drunkenness and sickness. The tendency to drink liquor (for example, mixed drinks or shots) faster than beer results in quicker intoxication. Moreover, although switching from liquor to beer is likely to decrease the rate of alcohol consumption, switching from beer to liquor is likely to increase it. And it is this higher amount that is the crucial contributing factor.  

Conclusion

Contrary to popular belief, simply mixing different types of alcohol is unlikely to make you sick–drinking a beer and a gin and tonic will probably have the same effect on your body as sticking to one type of alcoholic beverage.  However, drinking mixed drinks and shots means consuming greater amounts of alcohol at a faster rate, and you may become intoxicated before you know it. If you drink beer and then liquor, you will most likely get more drunk than you would have if you had started with liquor and felt the effects of alcohol earlier. If you ended up getting sick afterwards, you may have reasonably surmised that mixing the two types of alcohol in that order was the culprit. However, it was the total amount of alcohol consumed in a short period of time that most likely made you regret it.

Irrespective of your drinking itinerary, there are ways to decrease your risk of becoming ill or hung over. Having food in your system, for example, will absorb some of the alcohol so that it doesn’t go directly into the bloodstream, and it may protect your stomach from excess irritation. Alternating alcoholic beverages with water or juice will keep you hydrated and spread out the total amount of alcohol you drink. Finally, be aware that drinks in bars and restaurants may contain more alcohol than you think.